Fujitsu ScanSnap S300 Operator's Manual page 168

3. In the [PDF file format option] window, select [Generate one PDF file per x page(s)]
and enter a number.
One PDF file is created every time when the specified number of pages have been scanned.
HINT
4. Click the [OK] button to close the window.
⇒
The setting is enabled from next scanning.
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In Duplex mode, two pages (front/back) are created per document sheet. It is
recommended that you clear [Allow automatic blank page removal]; select the
[Scanning] tab [Option] button to open the window. If this function is
enabled, there may be a discrepancy between the page numbers of the original
document and the resulting document in which blank pages may be deleted.